Lathe-docs



UNITED STATES PATENT OFFICEo Joan wINsLow, JE., AND EoswELn nTKINs, OE BEIsTOI., CONNECTICUT.

I secure the rocking block d.

LATHE-DOG.

SPECIFICATION forming partxof Letters Patent No. 293,293, dated February 12, 1884. Application filed May 12, 1883. lNo model.)

ToaZZ whom it may concern.-

Be it known that we, JOHN VINSLOW, J r., and RoswELL ATKINs, citizens of the United States, residing at Bristol, in the county of 4Hartford and State of Connecticut, have invented certain new and` useful Improvements in Lathe-Dogs, of which the following is a specification.

Our invention relates to an improvement in lathe-dogs; and the object of our invention is` to enable a tapering piece to be grasped firmly, and at the same time to have the dog, when applied to such tapering piece, stand at right angle toits axis. We attain this object by the simple mechanism illustrated in the accompanying drawings, in whieh- Figure l is a side elevation of our improved lathe-dog. Fig. 2 isa section thereof, partlyin elevation, upon the two planes represented by the line rv x of Fig. l; and Fig. 8 is aseotion, partly in elevation, through the middle of the dog. Y A represents the body of the dog, the general form of which may be the same as that of any lathe-dog in ordinary use, and it `is provided rwith the set-screw a. Instead, however, of having the end of this set-screw aimpinge directly upon the work to be held in 'the dog, we form the ball b at its lower end, which enters the corresponding socket in the I rocking piece c, said piece being attached to end of the screw` by its ball-and-socket `joint, so as to remain permanently thereon. The

body A of the dog is recessed to make room for this rocking piece c, and the inner face'of the rocking piece c constitutes the surface which will be bound upon the work.

Directly Opposite the rocking piece c we This block has formed upon it, on. two sides, ears or trunnions j', which rest in the correspondinglyshaped sockets in the body of. the dog, and uponwhich the block d can rock freely. The

sides of the socket into which the trunnionsf are'received are closed together sufficiently to prevent the accidental withdrawal of the rocking piece d, whereby said piece is permanently Secured tothe body of the dog. When a cylindrical rod or shaft is dogged, the inner face of pieces c and d will be parallel to each other, as shown in Fig. 2, and the dog will hold the work substantially the same as any ordinary lathe-dog, excepting that the setscrew does not impinge directly upon the work.

B designates a tapering'piece of work as held within the dog, and represented in Fig. 3, in which view it will be seen that the pieces c and d rock or tip to conform to the taper of the work, while the body of the dog stands at right angles to the axis of the shaft B, precisely the same as it would ifa piece with cylindrical or straight sides were dogged. To enablethe tapering piece to be thus dogged is a convenience which will be readily-appreciated by all machinists..

We are aware that prior patents show a lathedog as made with a box at the end of the screw substantially like the box for the bearing in a lathe, but without any rocking capacity, said block being guided in a dened course by means of waysor guides; also, one in which the endof the set-screw is steadied and guided in its path by Ineans of across-bar sliding in ways or guides, but without any rocking movement, and with the end. of the screw projecting through the bar; also, that other patentsshow what is known as clampdogs, composed of two bars and two screws,

with rocking pieces upon the confronting faces of the two bars and between the screws. All of this prior art is hereby disclaimed.

` We claim as our inventionl. Thelathe-dog herein described, having the rocking piece c permanently secured to specified.

JOHN WINSLOW, JR. ROSWELL ATKINS. Vitnesses:

BENJ. F. HAWLEY, /JAMEs A. MATnEws. 

